Researchers in Switzerland have built a perfusion machine that can preserve human livers for transplantation for a week or more, potentially slashing the number of donor livers that must be discarded due to time-related deterioration.
Existing perfusion technology can preserve a donor liver for up to 24 hours.
The team of surgeons, biologists and engineers at University Hospital Zurich said their liver perfusion machine integrates core physiological functions, including automated glucose and oxygen management, waste-product removal and hematocrit control. The research is part of the Wyss Zurich “Liver4Life” project, and the study was published in the journal Nature Biotechnology.
The machine continuously moves the liver in an effort to mimic diaphragm oscillations. It is also fully automated, obviating the need for constant presence of personnel. The researchers first tested the machine on pig livers, then on 10 severely injured human livers that had been rejected by all European transplant centers, according to the study. After a seven-day perfusion, six of the human livers were producing bile, synthesizing coagulation factors, maintaining cellular energy and remained intact. They even healed from injuries and inflammation that occurred before or at the beginning of the perfusion process, the study said.
The researchers posited that such long-term perfusion may one day enable:
- Repair of severely fatty livers.
- Lowered odds of organ rejection.
- Chemotherapy that would be too toxic for the rest of a patient’s body.
- Long-distance transportation of organs to improve worldwide organ-sharing and transplantation logistics.
- Liver regeneration, with a donor liver split into several anatomic segments to regrow in the machine.
“Recent surgical procedures have shown that massive liver regeneration in humans can occur within 6 (days) of major tissue loss,” the researchers wrote. “If feasible, such an approach could double or even triple the availability of organs for transplantation. We may also imagine the use of partial grafts for auto-transplantation in patients with liver cancer, obviating the need for immune suppression.
“With further testing to demonstrate its use with injured livers and long-term transplantation success, this machine may provide an avenue for providing more patients with liver grafts,” they concluded.